Short
Term Effects of Cannabinoids (THC Marijuana Cigarette) on HIV-1 Viral Load

For
background information, Donald Abrams, MD, University of California at San
Franceisco, discused in his late breaker poster at Durban how canniboid use
could potentially alter HIV viral load levels by 2 mechanisms--immune modulation
or interactions with protease inhibitor because both share cytochrome P450
metabolism pathways. Anecdotal benefits to
appetite stimulation and stress relief (amongst other effects) encourage use of
marijuana amongst HIV-positive people living in California and this stimulated
Abrams to conduct this study.

This
was a randomized, partially blinded, placebo controlled 21-day inpatient study.
HIV positive patients on a stable indinavir or nelfinavir regimen were
randomized to one of three arms--3.95% THC marijuana cigarette, oral dronabinol
( an oral form of the active ingredient in marijuana), or an oral placebo. HIV
viral load was measured often--twice at baseline and at weeks 2, 5, 8, 11, 14,
17, 19, and 21. The HIV viral load was <50 copies/ml for 37 (55%) of patients
at baseline and the median CD4 was 300. However, 7 individuals had viral load
>10,000 copies/ml, and 13 had viral load 500-9999 copies/ml. Prior use of
marijuana was required to qualify for the study but no use was permitted for the
month prior to beginning the study. 63 patients completed the 21 day hospital
stay. On average, patients who smoked or took oral dronabinol had greater
decreases in viral load between day 0 and day 21 than patients on placebo but
the difference was not very much (-0.15 log, p=0.11, vs.-0.19 log, p=0.13 ),
after adjusting for baseline viral load, CD4 count, and protease inhibitor. 12
of 62 individuals had increased viral loads of <1 log: 5 (25% in the
marijuana arm, 2 (10%) in the dronabinol arm, and 5 (25%) in the placebo arm.
Three individuals discontinued from study (1 marijuana, 2 oral dronabinol) due
to neuro-psychiatric symptoms. No adverse events were reported in the placebo
arm.

Interestingly, the average calorie intake was
higher in the marijuana smoking, and oral dronabinol arms than in the placebo
armŮ 4700,4100 and 3600 calories a day in the marijuana, dronabinol and
placebo arms respectively. This lead to an average weight gain of 3.5,3.1 and
1.3 kgs over the three week study period. So, patients receiving smoked or oral
marijuana gained more weight than those receiving placebo.

It
appears 3-4 weeks ought to be adequate to test a potential change in viral load
with herbals but it would have been helpful if the study conducted PK (blood
levels) parameters before and after marijuana was used to see if blood levels
changed after adding marijuana. One cautionary note I would offer is that this
study was not conducted with ordinary "pot" purchased from the normal
sources people buy pot. It sounds as if the study used "pharmacuetical"
grade pot and oral pills.